Gas Diffusion Simulation in Porous Materials

Solution Overview

Problem

Existing gas diffusion simulation methods for porous materials are inefficient due to combining pore wall collisions and gas particle collisions in a single Boltzmann equation, leading to long simulation times and inaccurate results, especially when assuming uniform cylindrical pores.

Innovation Solution

A method that calculates the Knudsen diffusion coefficient based on the mean square displacement of gas particles and combines it with an interdiffusion term using an interdiffusion coefficient to simulate gas diffusion in porous materials, allowing for precise simulation in a shorter time by defining diffusion spaces with actual wall surface positional information.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single Boltzmann equation is used to simulate gas diffusion by combining pore wall collisions and gas particle collisions, then the simulation model is simplified, but the simulation time increases and precision decreases

Engineering Contradiction:

Improvesimulation model complexityVSAvoidsimulation time

Core Design Contradiction:

Device complexityVSLoss of time

Solution Approach 1:

The patent segments the gas diffusion simulation into two distinct components: Knudsen diffusion (pore wall collisions) and interdiffusion (gas particle collisions). Each component is calculated separately using its own diffusion coefficient, allowing for more efficient and accurate computation compared to a unified Boltzmann equation approach.

Inventive Principle:

Principle #1Segmentation

2Device complexity

If a single Boltzmann equation is used to simulate gas diffusion by combining pore wall collisions and gas particle collisions, then the simulation model is simplified, but the simulation precision decreases

Engineering Contradiction:

Improvesimulation model complexityVSAvoidsimulation precision

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

The patent segments the gas diffusion simulation into two distinct components: Knudsen diffusion (pore wall collisions) and interdiffusion (gas particle collisions). Each component is calculated separately using its own diffusion coefficient, allowing for more efficient and accurate computation compared to a unified Boltzmann equation approach.

Inventive Principle:

Principle #1Segmentation

3Ease of manufacture

If uniform cylindrical pores are assumed in the simulation, then the calculation process is simplified, but the accuracy of diffusion simulation decreases

Engineering Contradiction:

Improvecalculation simplicityVSAvoiddiffusion simulation accuracy

Core Design Contradiction:

Ease of manufactureVSMeasurement precision

Solution Approach 1:

The patent applies local quality by using actual porous material geometry information (obtained from tomography or other measurement methods) to define the pore structure. This allows the simulation to account for the true local characteristics of the porous material rather than assuming uniform cylindrical pores, significantly improving accuracy while maintaining computational feasibility through modern imaging techniques.

Inventive Principle:

Principle #3Local quality

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enables highly precise gas diffusion simulations in porous materials by accurately modeling Knudsen and interdiffusion processes, reducing simulation time and improving precision by using actual porous material geometries and considering liquid water presence.

Implementation Method 1

calculating, in the pores, a Knudsen diffusion coefficient based on the mean square displacement of first gas particles in spaces surrounded by wall surfaces and a Knudsen diffusion term using the Knudsen diffusion coefficient

Methodology Applied

Scientific EffectKnudsen diffusion: Diffusion

Implementation Method 2

calculating an interdiffusion term using an interdiffusion coefficient between the first gas particles and second gas particles different therefrom

Methodology Applied

Scientific EffectInterdiffusion: Diffusion

Data Source

PatentUS11549875B2Gas diffusion simulation method and apparatus therefor

Publication Date: 2023.01.10 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD

AI summary

A gas diffusion simulation method for simulating diffusion of a gas in a porous material having many pores, the method includes: calculating, in the pores, a Knudsen diffusion coefficient based on the mean square displacement of first gas particles in spaces surrounded by wall surfaces and a Knudsen diffusion term using the Knudsen diffusion coefficient, calculating an interdiffusion term using an interdiffusion coefficient between the first gas particles and second gas particles different therefrom, and performing simulation of the gas diffusion of the first gas particles by using a diffusion equation of the first gas particles represented by the sum of the Knudsen diffusion term and the interdiffusion term.